뚱냥냥냥 스토어

뚱냥냥냥

개인인증

팔로워0 팔로우

소개

등록된 소개글이 없습니다.

전문분야 등록된 전문분야가 없습니다.

판매자 정보

학교정보

입력된 정보가 없습니다.

직장정보

입력된 정보가 없습니다.

자격증

입력된 정보가 없습니다.

판매지수

판매중 자료수

16개
전체 판매량

5개
최근 3개월 판매량

0개
자료후기 점수

평균A
자료문의 응답률

-

전체자료 16개

판매자 표지

pre report-해수의 전기전도도 측정

1.The purpose of experimentTo know the meaning and principle of the electrical conductivity and measure it.2.Theory1)The conductivity of the solutionIt indicates the extent that the electric current flow well or not at the material. It is inverse of the resistivity. It is the intensive variable that can change. (pressure, temperature, concentration, density, melting point, boiling point)

공학/기술| 2022.06.10| 2페이지| 2,500원| 조회(112)

경희대, A+, 화학공학과, 화공과, 2실, 화기설

미리보기

닫기
판매자 표지

post report-해수의 전기전도도 측정

Title : measure the electrical conductivity of sea water1.AbstractAfter making arbitrary sea water with the distilled water and the NaCl, measure the electrical conductivity of the distilled water, the sea water and the taped water. The reason of measuring electric conductivity is to know the purity of the samples.2.Introduction1) The electrical conductivityThe electrical conductivity of the solution is the performance of the solution that makes to flows electricity. It is one of the means that evaluate the ionic strength. For that, the ions are needed. As they move the charges so make to flow electricity. The electric conductivity is the inverse of the resistance.R=pl/S (p:resistivity, S : cross-section area, l: length) p=100/58C (C=conductivity)2) Ionic strength(I)The ionic strength is the function of all ions’ concentration. It is related to the ions’ concentration in solution.The ci is the mole concentration of ion and zi is the ionic charge. In other words, the mole concentration heating. Generally the distilled water is made with the taped water. When the taped water heats so the water vapors occurs, by cooling them the distilled water is produced. Before water heating, the water is composed of lots of the impurities. They can be CO2, salts, metal etc. But by just one distillation, the all of impurities can’t be removed completely. In case that the distilled water with higher purity is needed, several times distillations are done. Up to how many distillation are done, distilled water is divided to the primary, secondary, tertiary distilled water.3.Result and discussionThe electric conductivity of the solution is the one of means of evaluating the ionic strength so it is proportionate to the ionic strength. The electric conductivity of the solution is related to the ions in the solution. On the other side it is natural since the ions move charge so make electricity flow. The ionic strength is the sum of multiplication the mole concentration and the charge of ioirst related to the temperature. The kinetic energy is and is proportionate to the temperature. Also the energy is : i.e. This means that the velocity is proportionate to the temperature.To sum up, the ionic mole concentration, the ionic charge, and the ionic velocity affects to the electrical conductivity. The ionic velocity is related to the temperature. And the rest are related to the ionic strength.Also I think the distance between electrodes and the cross-section area affects to the electrical conductivity. The conductivity is the inverse of the resistance.(R=pl/S) Therefore the electrical conductivity is S/pl. I think that the cross-section area is bigger and the distance among the electrodes is shorter, the electrical conductivity is bigger. Therefore the distance among the electrode and the resistivity of the electrode can be factors that affects to the electrical conductivity.At the experiment. The measured electrical conductivity of the distilled water is 2.50㎲/㎝. Theoreticaler. They transport the charge so makes the electric current flows. As a result, the impurities not removed completely so remained in the distilled water may make the little electric current.At the experiment, the electrical conductivity of the taped water and the artificial sea water is each 217.7 ㎲/㎝ and 53.5㎳/cm. Their measured value are larger than the distilled water as the more impurities are in their solution. In other words, the more charge carriers are so the electrical conductivity is measured higher than the distilled water. Also the electrical conductivity of the artificial sea water is measured larger than the taped water. This means the more charge carriers are in the artificial sea water. As a result, the mole concentration of the impurities(ions) is the artificial sea water> the taped water> the distilled water in the decreasing order so the electrical conductivity is also too.4.ConclusionThe electrical conductivity is the inverse of the resistance. It indicates the exte-section area of the electrode and distance between the electrodes. Therefore, the mole concentration of impurities(ions) is artificial sea water> the taped water> the distilled water in the decreasing order so the electrical conductivity is also too. Theoretically, the electrical conductivity of the distilled water should be 0 as it is refined so the impurities can’t exist. Despite the distillation, the little impurities can exist in the distilled water so the little electrical current flows.5.Reference Hyperlink "https://www.scienceall.com/%EC%A0%84%EA%B8%B0-%EC%A0%84%EB%8F%84%EC%84%B1electrical-conductivity/" https://www.scienceall.com/%EC%A0%84%EA%B8%B0-%EC%A0%84%EB%8F%84%EC%84%B1electrical-conductivity/ Hyperlink "https://terms.naver.com/entry.nhn?docId=5145271&cid=61234&categoryId=61234" https://terms.naver.com/entry.nhn?docId=5145271&cid=61234&categoryId=61234 Hyperlink "https://terms.naver.com/entry.nhn?docId=5145271&cid=61234&categoryId=61234" https://terms.naver.com/entry.nhn%BC

공학/기술| 2022.06.10| 3페이지| 2,500원| 조회(140)

경희대, A+, 화학공학과, 화공과, 2실, 화기설

미리보기

닫기
판매자 표지

pre report-용액의 pH 측정

Title : Measure the pH of the solution with pH meter1.AbstractUsing the pH meter, measure the pH of the solution. Before that, calibration with the pH buffer 4.00, 7.00, 10.00 so set up the reference value. After that, measure the pH of the distilled water, ionic beverage, the juice.2.Introduction#The reason that the pH balance is importantpH is the means that indicate the activity of the protons. The pH is also important factor for the water treatment(chemical cohesion, sterilization disinfection, corrosion, softening). For example, the pH change can effect to the dissociation of the toxic substance. When the pH is low, the chemical equilibrium moves to increase the proton.(the example of toxic substance : HCN). Therefore, HCN dissociates more well so the toxicity increases.We can find out the pH in our body. The pH of our body is about 7.3~7.4, and our body has the buffer system to prevent of the sharp pH change. The ideal pH differs up to the organs. For example, the optimal pH of tatelier’s principle : When the concentration, temperature, volume, pressure changes at the chemical system in the chemical equilibrium, the chemical equilibrium moves to decrease the change. The buffer solution is also same.The principle of it is the common ion effect. It is based on the Le Chatelier’s principle : When the common ion is added (the ion is the same ion that is in the solution at the equilibrium), the equilibrium moves to decrease the concentration of the common ions.For example, there are the CH3COOH and CH3COO-.CH3COOH (aq) ↔ CH3COO-(aq)+H+(aq) (↔=indicates this reaction is the reversible reaction.)When the proton is added to the buffer solution, it reacts to the CH3COO-. Therefore, CH3COOH is made and the concentration of the H decreases. By the Le Chatelier’s principle(the common ion effect), the chemical equilibrium moves to increase the H+ so compensate it. Therefore, the pH keeps almost constant.. In other words, the buffer solution works.3.Result and discussionTher and sample same at the experiment.I think the second factor is the extent that the solution dissociates well or not.(degree of ionization). It related to the intensity of the base and acid. The degree of ionization is the ratio the ionized electrolyte mole to the dissolved the electrolyte mole at the electrolyte’s aqueous solution. (This solution is in chemical equilibrium.). It ranges from 0 to 1. The value “1” means the total, most electrolytes ionized.By the degree of ionization, the acid is divided to the strong acid and the weak acid. The strong acid is mostly ionized but the weak acid is not well ionized. The base is also too. As the pH=-log[H+], the strong acid puts out many protons most so the acidity is the highest. (pH is lowest.) The next is the weak acid and weak base. And the last strong base puts out many hydroxide ions so the basicity is the highest. (pH is highest)I think the third factor is the concentration of CO2 in the air. If it dissolves in the water, it becomesexperiment, measure the pH of the distilled water, the ionic beverage, the grape juice. The theoretical pH of the distilled water is 7 and the measured pH is the 7.03. And the pH of the ionic beverage, grape juice is each 3.34, 3.09. They are weak acidic.Although the ionic beverage is called as the alkali beverage, the measured pH indicates that it is weak acidic. It is made for athletes. During workout, the water and the electrolyte are ejected. The electrolytes are important cause they act as cofactor that helps the activity of enzymes or controller of the pH and they are related to the neurotransmitting. Therefore, their composition is similar to the body fluid. The body fluid is composed of the most water, salts, amino acids, hormones, glucoses, and additives to offer the lost water and mineral(electrolyte).At the experiment, the measured pH of the ionic beverage is about 3.34(acid) although it is called as the alkali beverage. Despite of the alkali metal ions, the reason that it ity decreases. The pH not changes largely.4.ConclusionI think the affecting factors to pH are temperature, the degree of ionization, the concentration of CO2, and filtering of organisms. But the fundamental factor is the concentration of proton in the solution. If pH changes sharply, it affects to the vital things like activation of enzyme so the buffer must be needed. The principle of buffer is common ionic effect(Le Chatelier’s principle). It is composed of the weak base and the conjugate acid or the weak acid and the conjugate base. By the common ionic effect, if the concentration of proton decreases or increases, the chemical equilibrium moves to prevent the change so the pH not changes sharply.5.Reference Hyperlink "https://ko.wikipedia.org/wiki/%EB%A5%B4_%EC%83%A4%ED%8B%80%EB%A6%AC%EC%97%90%EC%9D%98_%EC%9B%90%EB%A6%AC" https://ko.wikipedia.org/wiki/%EB%A5%B4_%EC%83%A4%ED%8B%80%EB%A6%AC%EC%97%90%EC%9D%98_%EC%9B%90%EB%A6%AC Hyperlink "https://ko.wikipedia.org/wiki/%EC%99%84%EC%B6%A90261

공학/기술| 2022.06.10| 4페이지| 2,500원| 조회(110)

경희대, A+, 화학공학과, 화공과, 2실, 화기설

미리보기

닫기
판매자 표지

post report-Abbe굴절계를 이용한 굴절률 측정

Title : Measure the refractive index with the Abbe refractometer1.AbstractThe refractive index with the Abbe refractometer is the specific temper so determine the physical temper of the solution.2.Introduction1) refractive index : the snell’s lawWhen the light passes by the boundary surface, the situation that the light direction of progress changes is called “refraction”. It is because the velocity of wave progress differs up to the medium. The reason that the velocity of the light differs is the difference of the density. The density is the mass per volume. In other words, it is the amount of the particles per volume. (mass=mole*molecular weight) The density is larger, the more particles exist in the same space. This makes the change of the velocity.The refractive index is defined by the snell’s law.2) The electromagnetic radiation, EMRIt is the wave that the vibration of the electric field and the magnetic field progresses at the space. The light is one of the electromagnetic radiation. At the space that the material not exist(vaccum), all the electromagnetic radiation progresses with the luminous flux.The velocity of the electromagnetic radiation is the same.3.Result and discussionThe factors that affect to the refractive index is wave length(the light source), temperature, pressure, the material density, and the mass fraction(wt%) .The first factor is the wave length.(light source). The light sources have the different wavelength but the same velocity. The wavelength of wave generally differs up to the materials. The is the same with the f in the vaccum(The frequency not change when the radiation go to the other material.), and the light velocity is always smaller than the vacuum light velocity Therefore the wavelength reduces corresponding to that.This combines with the .Therefore, the wave length of the radiation is larger, the refractive index is reduced.The second factor is the temperature. This changes the change of the density so affects to the refractive index. When the temperature increases, the molecules move actively more. Since the kinetic energy increases. () Therefore, the volume is larger. The density is smaller since the mass same but the volume is larger. For that reason, the density is smaller so the refractive index increases. In other words, the volume larger so the radiation can move easily.And the third factor is the material density. Up to the materials, each density differs since the density is the specific temper. The density is the mass per volume : i.e. particles per volume. The density is larger, the more particles exist in the same space so makes the change of the velocity more as radiation moves harder at the liquid that has higher density.The fourth factor is the pressure. It is reverse to the volume. If the pressure increases, the volume is reduced. Or the pressure decreases, the volume increases. If exert pressure to the solution, the density of the solution increases. Since the volume is reduced by the pressure but the mass is same. Therefore, the pressure of the solution is lower, the refractive index is lower.The last factor is the mass fraction for the same volume. The reason is similar to the material density. For the same volume solution, As the mass fraction of the materials(at the experiment, EtOH) increases, the refraction index increases too. This reason is the higher mass fraction with the same volume solution has the more particles for the same volume solution. Thus, the density is larger so the radiation moves harder and the velocity changes largely. The more mass fraction of the particles in the solution, the refractive index is larger.Therefore, the mass fraction of EtOH is larger, the refractive index is larger. When draw the graph based on the data, the graph that is estimated : . Using the graph, the refractive index of X is 1.344. Therefore, the mass concentration (wt%) of the x is about 13.45%.4.ConclusionThe factors that affect to the refractive index is the wave length(the light source), temperature, the material density(solution), pressure and the mass fraction(wt%) in the solution.The mass concentration (wt%) of the x is about 13.45%.5.Reference Hyperlink "https://terms.naver.com/entry.nhn?docId=1067924&cid=40942&categoryId=32235" https://terms.naver.com/entry.nhn?docId=1067924&cid=40942&categoryId=32235 Hyperlink "https://terms.naver.com/entry.nhn?docId=4390132&cid=60217&categoryId=60217" https://terms.naver.com/entry.nhn?docId=4390132&cid=60217&categoryId=60217한국물리학회, 물리학백과 한국천문학회, 천문학백과

공학/기술| 2022.06.10| 3페이지| 2,500원| 조회(114)

경희대, A+, 화학공학과, 화공과, 2실, 화기설

미리보기

닫기
판매자 표지

pre report-Abbe굴절계를 이용한 굴절률 측정

Title : Measure the refractive index with the Abbe refractometer1.The purpose of experimentThe purpose of the experiment is to know about the measuring the refractive index with the Abbe refractometer and to predict the concentration of the sample.2.Theory1)refractive index : the snell’s lawWhen the light passes by the boundary surface, the situation that the light direction of progress changes is called “refraction”. It is because the velocity of wave progress differs up to the medium.This pictures show that the ray of light coming to the boundary. The some of the ray reflects at the boundary and other pass get through it and is refracted. To know aboutThe refractive index is the ratio that the luminous flux is reduced when the light goes into the transparent medium. The refractive index is expressed with “n” generally.To know the extent that the ray of light is refracted(refractive index), using the snell’s law.The reason of measuring the refractive index is to determine the physical scale, criteria that indicates the intrinsic temper like the density of the solution(medium) and the characteristics of the molecules by passing the light through.2)Fermat’s principleIt is the principle that the light starting at the some point go to the other point, the path of light is path that the light takes for the shortest time of lots of courses. Therefore the light ray is refracted when go through the other medium.3)Abbe refractometerIt is the refractometer that measures the refractive index of the astrological body. Make two right prisms that are inclined face each other and then make the thin layer of sample between them. After it, bring convergent light flux to the layer so measure the angle of emergence to the critical angle so measure the refractive index of the sample(liquid).#principlePut the samples in the space between two rectangular prisms. The upper side of one of prism is rough so make the light scattering so pass through the all directions of liquid. On the otheted and go through the other prism. This light is refracted one more at the boundary of the air so get in the microscope. The light and shade is observed at the visual range of telescopes so adjust it to the cross line. At that time, the marking indicates the refractive index of samples.#Component eq oac(○,1)MicroscopeIt is composed of the round plate that nosepiece, eyepiece, the focus plate of nosepiece. This forms the pictures of total reflection at the boundary within the plate of cross-line. The intersection point of cross line offers the point that brings the boundary into line. eq oac(○,2)Abbe prismIt is the prism that set the picture rightly for the microscope and use the roof type of reflection surface not to make the difference of optical axis between the optical lens and the objective lens. The direction of light ray that go through prism not change after going through prism. To control and keep the temperature by circulating the water around the prism, 2 prisms are compd, but the upper surface of the bottom surface is made of fine powder. The surface with powder sends the lay passing through prism to the all angle.The bottom prism is attached to the ribband of the upper prism with hinge. If the bottom prism is attached to the upper prism with pincers, the folded surface is separated with the thickness 0.1~0.15mm and the sample is filled in this space. eq oac(○,3)sectorIt is the metal rod that fix the microscope strongly. It connects the rest part of the refractometer to rotate the line sector around the axis that matches the rotation axis of Abbe prism.3.Experiment∙Reagent and instrument : Ethanol, the distilled water, the 100㎖ beaker, agitator, Abbe refractometer, constant temperature bath(1)Manufacturing the Ethanol solutionManufacture the 0wt%, 20wt%, 40wt%, 60wt%, 80wt%, 100wt% Ethanol 100㎖ solution.The density of Ethanol is 0.79g/㎖ and the water 1g/㎖.(2)The Method of the Abbe refractometer eq oac(○,1)Clean the prism by the cotton with alcoho eq oac(○,2)Connect the cover of prism and the constant temperature bath to purify the water eq oac(○,3)Lift up the prism and drop the sample solution 2~3 drops at the bottom. After it, fix by covering the prism. eq oac(○,4)Move the prism with adjusting screw until the visual range of telescope becomes the light part and the dark part 5:5. eq oac(○,5)Make the line that separate 5:5 exist at the intersection point correctly. eq oac(○,6)Read the marking eq oac(○,7)Whenever the measuring of one sample finish, clean the prism and the bottom lightly and 3~4 times with alcohol cotton.4.References Hyperlink "https://ko.wikipedia.org/wiki/%EA%B5%B4%EC%A0%88%EB%A5%A0" https://ko.wikipedia.org/wiki/%EA%B5%B4%EC%A0%88%EB%A5%A0 Hyperlink "https://terms.naver.com/entry.nhn?docId=1067924&cid=40942&categoryId=32235" https://terms.naver.com/entry.nhn?docId=1067924&cid=40942&categoryId=32235 Hyperlink "https://terms.naver.com/entry.nhn?docId=4390132&cid=60217&categoryId=60217" https://terms217

공학/기술| 2022.06.10| 3페이지| 2,500원| 조회(110)

경희대, A+, 화학공학과, 화공과, 2실, 화기설

미리보기

닫기